The broad objectives are: 1. To obtain structural information regarding the disposition of acetylcholine receptor subunits in the post-synpatic membrane and to delineate any possible interactions with the cellular cytoskeletal structure. 2. To study acetylcholine-acetylcholine receptor interactions in terms of equilibrium and kinetic properties, location of cholinergic ligand binding sites and sites for other ligands such as local anaesthetics. 3. To probe the properties of the molecular apparatus(ion-channel) responsible for flux of cations in response to acetylcholine binding and to relate this to divalent and monovalent cation binding sites. 4. To reconstitute a well defined receptor and lipid containing membrane suitable for studies of ion-flux and membrane potential changes in the millisecond time range.